(1) Field of the Invention
The present invention relates generally to lighting fixtures and, more particularly, to an outdoor lighting fixture for mounting a pair of floodlights or the like having a sealed swivel unit.
(2) Description of the Prior Art
Outdoor floodlights have been known for many years. In such devices, it is con, non to provide a mechanism in the mounting whereby the direction of the light may be adjusted at least to a limited degree. A common manner in which this is accomplished is by providing a connection between the light fixture and the base by which the fixture may be moved relative to the base and then secured against further motion.
In order to keep the lighting fixture in its selected position, pivotable devices such as thumbscrews and special clamps have been used. Swivel units also have been utilized for such a flexible connection with the construction of the swivel unit being such that the lighting fixture is pivotable about one axis through substantially 90.degree. and pivotable about a second axis at right angles to the first axis through substantially 360.degree.. This combination of pivotable movements enables the fixture to direct light over selected portions of an extensive area.
One type of swivel adjusting lighting fixture utilizes a sphere clamped between two plates thereby causing the sphere to be under compression and allow the sphere to rotate between the plates. The drawback with this type construction is that the wiring of the device is not sealed and therefore, if the device is used outside, moisture and rain may contact the wiring connections and cause a short.
U.S. Pat. No. 4,333,132, issued to Paley, discloses a manually controlled, environmentally sealed swivel unit for use in an adjustable lighting fixture. The swivel unit comprises a base, a housing, a swivel ball device and a means for controlling the rotation of the swivel ball. This arrangement allows the swivel ball to rotate about a first axis and also to rotate about the second axis perpendicular to the first axis. The swivel unit further includes a tension means for forcing the swivel ball controller against the swivel ball device to define a predetermined lamp holding force.
The Denison patent (U.S. Pat. No. 5,086,379) and the Snyder patent (U.S. Pat. No. 3,278,203) disclose two additional examples of swivel or ball-and-socket type joints used in lighting fixtures.
Certain disadvantages become apparent in reviewing these references. In particular, such devices are difficult to assemble and have a large number of parts or do not form an environmental seal. Thus, there remains a need for a new and improved outdoor lighting fixture having a sealed swivel unit including a semi-spherical knee ball cover and gasket combination which is used both to control the tension on the lamp holder ball and the freedom of movement of the knee ball while, at the same time, providing an environmental seal between the lampholder and base.